New York, March 8 (PTI): An Indian American doctor and majority owner of a Las Vegas clinic chain has surrendered his licence following a probe into allegations of medical malpractice, including reuse of syringes and vials, which may have put over 40,000 patients at risk.

The Nevada State Board of Medical Examiners had requested Dipak Desai — owner of Endoscopy Center of Southern Nevada, where six cases of hepatitis have been confirmed — to voluntarily stop practising medicine until its investigation was complete.

The board said Desai had agreed to surrender his licence but didnt give a time frame as to how long the investigation might take.

Another Indian doctor linked to the scandal, Vishvinder Sharma, also resigned from the state medical board but did not turn over his licence, local media reports said.

The FBI has joined the investigation for possible Medicare fraud. The agency will investigate whether the clinic billed Medicare for 30-minute appointments that did not last that long.

The clinic may have also committed fraud by billing Medicare for two vials when only one was used, officials said.

As many as 40,000 people may have been infected with the deadly hepatitis C virus or HIV from the clinic over the last four years, officials said, adding six of Desais facilities had been closed.

Desai, who has been practising medicine in Nevada for 28 years, is reportedly an alumnus of Gujarat University.

Four other clinics have been discovered reusing syringes, officials said. Investigators will check 30 other clinics in the state.

Nevada will also get federal help on Tuesday when Center for Disease Control agents will assist in the inspections.

Desais facility became the focal point of a massive health alert when officials found staffers reusing syringes and vials containing anaesthesia medication.

Nevada authorities had issued a health notification urging thousands of people who had used the facility to get tested for infections.

So far, six cases of hepatitis C have been confirmed.

Larry Matheis, the executive director of the Nevada State Medical Association, said he believed Desais decision to stop practising was appropriate.

That is a good step, he said.

Desais move came two days after five nurse anaesthetists associated with his clinics voluntarily surrendered their licenses at the request of the state nursing board.